MEXICO CITY - Mexico is battling billionaire drug mafias armed with bazookas, but when President Felipe Calderon ranks the threats his country faces, he worries more about methane gas, dwindling forests and dirty refineries.

Calderon is a climate wonk. Who knew?

At a summit meeting last month attended by the leaders of Central America and Colombia, Calderon spoke of the hemispheric struggle against drug traffickers - and then proceeded to talk passionately about the Mesoamerican Environmental Sustainability Strategy.

"He is obsessed by climate change," said one of his press advisers, who claims that his boss enjoys discussing incandescent light bulbs - and don't get him started on thermoelectric power generation.

Calderon hopes to play a leading role as host of the United Nations climate conference starting this week in Cancun, where he will advocate a "third way" for developing countries such as Mexico: making commitments to serious, verifiable reductions in greenhouse gases in exchange for billions in aid and technology transfers from big polluters such as the United States and European Union.

"The president is extremely engaged and very committed. He has instructed us to move, and move now, and not wait for anybody else," said Fernando Tudela, the deputy secretary of planning and environmental policy.

Mexico is raising efficiency standards and helping citizens replace old refrigerators and air conditioners that don't meet them. It is ratcheting up mandatory emissions controls for vehicles and struggling to reduce the number of aging, heavily polluting buses on its roads. Government lenders are offering "green mortgages" with lower interest rates to home buyers who insulate windows or install solar panels.

Officials are having landfills covered to trap methane gas and planning power plants fueled by garbage; the first such plant will be built in Monterrey. The state oil company, Pemex, has promised to slash the amount of methane it wastes at its refineries by creating cogeneration energy plants.

By 2012, if it stays on track, Mexico will have reduced its carbon dioxide emissions by 50 million tons, equal to the carbon produced by 45 days of domestic oil production.

Mexico is the only developing country that has produced full inventories of all its greenhouse gas emissions.

The country of 110 million people, which stretches from northern deserts to southern jungles and has extensive coral reefs off its shores, is especially vulnerable to climate change. It is also a major agricultural, manufacturing and oil producer. According to U.N. estimates, Mexico, with the 14th-largest economy in the world, contributes between 1.5 and 3 percent of global emissions.

While Mexico is acting now to reduce emissions, it promises really steep cuts if it gets some help. As its "aspirational target," the country has pledged to reduce its greenhouse gases from the year 2000 level, which was 644 million tons, by 30 percent by 2020 and 50 percent by 2050.

"These are very ambitious goals, and yes, it is going to be tough, but Calderon and Mexico have a serious program, and they have gotten out in front of other countries," said Ned Helme, founder and president of the Center for Clean Air Policy in Washington.

Mexico hopes to be first at the table to grab some of the $30 billion in "fast start" financing promised by Europe and the United States to help developing countries control emissions. The $30 billion amounts to 10 times the resources previously available for developing countries.

"Europe and the U.S. are looking for success stories," Helme said, "and Mexico is emerging as a good place to make a bet."

Mexico is a major oil producer, but now it is exploring alternative energy as well. Its winds are rated Class 5, among the most reliable levels for power generation. In a joint venture with Spanish utility company Iberdrola, Mexico is building a massive wind farm in the southern state of Oaxaca.

The country also is a major maker of cement, which is a dirty business because the kilns burn the dirtiest, cheapest fuels, such as oil sludge. Cement makers are now exploring ways to burn sewage and other fuels in redesigned, cleaner kilns.

Mexico also is fighting to preserve its forests. It is working on partnerships with organizations such as the Nature Conservancy, World Wildlife Fund and Conservation International to protect trees and watersheds and to improve the lives of local residents, who are being steered away from slash-and-burn agriculture.

In one pilot program, the nonprofit Conservation International, along with the coffee moguls at Starbucks, has been steering producers in the southern state of Chiapas toward shade-grown coffee, which preserves the trees in forests that harbor monkeys, tapirs and birds - and also makes a nice roasted bean.

This is not easy. For the locals, there is short-term gain in clearing forest land to grow corn or raise cattle, and there is a huge gap between Mexico's richest citizens and the 50 percent who live in poverty. Massive government reforestation campaigns, such as ProArbol, have mostly withered, derailed by corruption, incompetence and the planting of saplings that were not suited to the environment and quickly died.

Like others, the government of Mexico has a long tradition of announcing lofty ambitions - for education, against poverty - only to see the goals quietly forgotten over the long haul. And fighting climate change is a marathon, according to everyone.

"There is a huge potential for green growth in Mexico," said Tudela. "We would like to prove that a developing country can mitigate and adapt to climate change without hurting the economy. We want to prove that in Mexico."